In known fluidizable bed apparatuses of the kind referred to, in which in use both the bed of fluidizable particulate material and fluidizing medium for fluidizing the bed operate under pressure, e.g. from 6 to 7 bars, and at high temperatures, e.g. typically from 750.degree. C. to 800.degree. C., there arise several problems associated with the temperature attained by, and the strength of, the distributing system for supplying the fluidizing medium to the container to fluidize the bed of particulate material.
The present invention aims to provide a solution to the above-mentioned problems and other problems associated therewith.